Device for the transfer of movements and forces in particular in dobby looms

ABSTRACT

The invention relates to an apparatus for the transmission of movements and forces from deflection lever connected with a drive means onto at least one linearly movable element, particularly of a dobby weaving machine, whereby the deflection lever is supported rotatably about an axis, whereby the deflection lever comprises a first and a second lever arm arranged at an angle relative to one another, and whereby the force introduction of the drive means occurs on one of the lever arms. The pivoting movement of a deflection lever shall be converted into a linear movement with low frictional losses and wear. This is achieved according to the invention in that at least one of the lever arms ( 2; 3 ) is connected with a linearly movable element ( 18  or  19; 20 ) by means of a first and a second flexible band ( 11, 12; 13, 14 ), and whereby the two bands are arranged and secured in such a manner so that for each force introduction for the carrying out of a linear forward movement or for the carrying out of a linear return movement of the elements ( 18, 19, 20 ), respectively only one of the bands ( 12, 14  or  11, 13 ) is subjected to or loaded with a tension force.

[0001] The invention relates to an apparatus for the transmission of movements and forces, particularly in dobby weaving machines, according to the preamble of the patent claim 1.

[0002] The subject of the invention is a level or planar transmission for the transmission of linear movements and forces from a first movement direction into a second movement direction, or for the conversion or translation of a pivoting movement into a linear movement.

[0003] Deflection levers, which are supported rotatably about an axis and comprise at least a first and a second lever arm arranged at an angle relative to one another, are, for example, used for the changing of the movement direction. At least one lever arm is articulately connected on a linearly movable element, while the other lever arm is connected with a drive means. A disadvantage of this known construction is that it is not possible therewith to transmit from the deflection lever a purely linear movement onto the first element and a purely linear movement onto the second element, or to convert the pivoting movement of the lever arm into a purely linear movement. Due to the rotational movement of the deflection lever, in addition to the linear movement an undesired movement component along a circular path is generated, which in total leads to a rocking movement of the elements coupled thereto, which must be compensated through corresponding articulate connection and bearing support. A further disadvantage is that the articulate connection point between the elements and the deflection lever is subjected to great loads and wear, and must be regularly and thoroughly greased.

[0004] The object of the invention consists in presenting an apparatus for the transmission of movements and forces, which converts the pivoting movement of a deflection lever into a linear movement with small frictional losses and small wear. The apparatus shall particularly be suitable for use in dobby weaving machines.

[0005] The object is achieved according to the invention through the characteristic features of the patent claim 1.

[0006] In accordance therewith, it is essential according to the invention, that at least one of the lever arms of the deflection lever is connected with the linearly movable element by means of a first and a second flexible band, tape or strip, whereby the two bands are arranged and secured in such a manner that always only one of the bands is loaded by or subjected to a tension force.

[0007] Along therewith, the advantage is achieved that the element connected via the bands to the lever arm carries out an exact linear movement. Furthermore, the connection of the lever arm to the linearly movable element by means of the bands is characterized by low wear. The connection is play-free and is not subject to a continuous maintenance, as this is, for example, the case with a roller bearing connection.

[0008] Embodying features of the invention are disclosed in the dependent patent claims.

[0009] In accordance therewith, both lever arms can be connected with a linearly movable element, whereby the first lever arm is connected with the first element by means of a first and a second flexible band, and the second lever arm is connected with the second element by means of a first and a second flexible band.

[0010] Advantageously each lever arm comprises an end piece with a roll-off surface that is essentially circular arc shaped, on which the bands roll-off, whereby one end of the first band is secured at a suitable location of the end piece and one end of the second band is secured at a different suitable location of the end piece, whereby the bands cross each other and whereby the other ends of the bands are connected with the allocated element. Depending on the movement direction of the elements, respectively one band is loaded with or subjected to tension, while the other band is unloaded.

[0011] In a preferred embodiment, the bands are arranged lying in one another in such a manner so that these penetrate themselves in a crossing manner. The first band is wider than the second band, whereby the first band comprises a slot extending over a major portion of its length, and the width of the slot is larger than the width of the second band. Thus, the bands run crosswise into one another so that a high guidance stability of the connected elements arises.

[0012] According to another embodiment, the bands can be arranged next to one another. Thereby the bands are embodied with the same width.

[0013] The bands can be produced from every suitable flexible and loadable material, such as, for example, steel, synthetic plastic, or textile material. Also a combination of these materials for producing the flexible bands is conceivable.

[0014] The invention will be described below in connection with an example embodiment shown in the drawings.

[0015] It is shown by:

[0016]FIG. 1 a side view of the apparatus according to the invention;

[0017]FIG. 2 a side view of a band;

[0018]FIG. 3 a top plan view onto the first band;

[0019]FIG. 4 a top plan view onto the second band;

[0020]FIG. 5 the apparatus in the application in a shaft drive in dobby weaving machines in a first movement condition;

[0021]FIG. 6 the apparatus in the application in a shaft drive in dobby weaving machines in a second movement condition;

[0022]FIG. 7 the apparatus in the application in a shaft drive in dobby weaving machines in a third movement condition.

[0023]FIG. 1 shows the apparatus according to the invention, which is based on a deflection lever 1, as it is known, for example, for the deflection of movements and forces for heald frames or shafts in dobby weaving machines. The deflection lever 1 comprises two lever arms 2 and 3 arranged at an angle relative to one another, through which lever arms the movements and forces are input and output. The deflection lever 1 is supported pivotably about an axis 5 by means of a bearing 4. The deflection lever can further comprise a further bearing 6 for the force introduction or input.

[0024] The lever arms 2 or 3 respectively comprise an end piece 7 or 8. The end pieces 7, 8 respectively comprise a circular arc shaped roll-off surface 9, 10. Mutually crossing bands 11, 12 or 13, 14 are secured on the ends of the roll-off surfaces 9, 10, in that respectively one end of each band 11-14 is anchored or fixed on the end piece 7 or 8 by means of an attachment 15 or 16. The bands 11-14 preferably consist of spring steel, but may also be made of synthetic plastic or textile material. The free ends of the bands 11, 12 and 13, 14 are operatively connected with respectively one linearly movable element. The force input or output is achieved through these elements. This will be described in further detail below.

[0025] The FIGS. 2 to 4 show the bands in detail. FIG. 2 shows the form of the bands 11-14 as seen from the side. The bands can be pre-formed in such a manner, so that they correspond to the form of the roll-off surfaces 9, 10 of the end pieces 7, 8. The bands may, however, also be embodied straight and not pre-formed.

[0026]FIG. 3 shows a top plan view onto the first band 11 or 13. The band preferably has rectangular cross section and comprises a slot 17, which extends over a major portion of the band length. The second band 12 or 14 is, except for the attachment points at the ends, embodied narrower than the first band 11 or 13. The width of the second band 12 or 14 is somewhat smaller than the width of the slot 17 of the first band 11 or 13, and can thus be guided through the slot 17, whereby the crossing-over arrangement of the bands 11, 12 or 13, 14 arises, as this is shown in FIG. 1.

[0027] The FIGS. 5 to 7 show the apparatus according to the invention in the application for the shaft drive of a dobby weaving machine. Thereby various movement conditions are shown. Two deflection levers 1 a, 1 b, which are pivotably arranged on the machine frame (not shown), are connected with one another via a connecting rod (thrust/tension rod) 18. The force introduction or input is achieved over the bearing 6 of the right deflection lever 1 a, whereby the deflection lever 1 a carries out a pivoting movement in the direction of the double headed arrow 28. The bands 13, 14 of the lever arm 3 are secured to the connecting rod 18 by means of attachments 21, 22. A clamping or tensioning device 23 can be provided on an end of the connecting rod 18 for the clamping or tight tensioning of the bands 13, 14. The bands 13, 14 transmit the pivoting movement of the deflection lever 1 a onto the connecting rod 18, which, as a result, carries out a linear movement in the direction of the double headed arrow 26. The bands 13, 14 carry out a roll-off movement on the roll-off surface of the lever arm 3, whereby the roll-off point 31 remains fixed on an imaginary axis 29, while the roll-off surface 10 of the lever arm 3 moves past under the roll-off point 31. Because the roll-off point 31 does not vary or change, the pivoting movement of the deflection lever 1 a is converted into a purely linear movement of the connection rod 18.

[0028] The other lever arm 2 of the deflection lever 1 a is similarly connected with a connecting rod (thrust/tension rod) 20 via bands 11, 12, which connecting rod 20 drives the shaft of the dobby weaving machine, and is connected therewith through a shaft coupling 25. Here also, the pivoting movement of the lever arm 2 is converted into a linear movement of the connecting rod 20 in the direction of the double headed arrow 27. The roll-off point 32, see FIG. 6, similarly remains fixed on an imaginary axis 30, while the roll-off surface 9 of the lever arm 2 moves past under the roll-off point 32.

[0029] In a first movement process, only the bands 11 and 13 are loaded under tension, while the bands 12 and 14 are unloaded. If the movement direction reverses itself, then in the reversed manner, the bands 12 and 14 are loaded under tension and the bands 11 and 13 are unloaded.

[0030] The connecting rod 18 transmits the movement onto the second left deflection lever 1 b, which is similarly connected by means of bands with the connecting rod 18. Thereby the deflection lever 1 b is pivoted in the direction of the double headed arrow 28 and transmits this movement onto a further connecting rod (thrust/tension rod) 19, which is connected with the weaving machine shaft via a shaft coupling 24. The force transmission between deflection lever 1 b and connecting rod 19 here similarly is achieved by means of bands, whereby the connecting rod 19 is linearly moved in the direction of the double headed arrow 27.

[0031] Thus, advantageously, an oscillating pivoting movement of the deflection lever is transmitted as a purely linear movement onto corresponding movable elements, which is achieved by the use and the inventive arrangement of the flexible bands 11, 12 or 13, 14. 

1. Apparatus for the transmission of movements and forces from deflection lever connected with a drive means onto at least one linearly movable element, particularly in dobby weaving machines, whereby the deflection lever is supported rotatably about an axis, whereby furthermore the deflection lever comprises a first and a second lever arm arranged at an angle relative to one another, and whereby the force introduction of the drive means occurs on one of the lever arms, characterized in that at least one of the lever arms (2; 3) is connected with the linearly movable element (18, 19 or 18, 20) by means of a first and a second flexible band (11, 12; 13, 14), whereby the two bands (11, 12; 13, 14) are arranged and secured in such a manner so that to each force introduction for the carrying out of a forward movement or for the carrying out of a return movement of the elements (18, 19, 20), respectively only one of the bands (12, 14 or 11, 13) is subjected to a tension force.
 2. Apparatus according to claim 1, characterized in that the lever arm (2) is connected with the linearly movable element (19, 20) and the lever arm (3) is connected with the linearly movable element (18), whereby the connection of the first lever arm (2) occurs by means of the first and second flexible bands (11, 12) and the connection of the second lever arm (3) with the element (18) occurs by means of the first and second flexible bands (13, 14).
 3. Apparatus according to claim 1, characterized in that the lever arms (2, 3) comprise an end piece (7, 8) with an essentially circular arc shaped embodied roll-off surface (9, 10), on which roll-off surface the bands (11, 12; 13, 14) roll-off.
 4. Apparatus according to claim 1, characterized in that an end of the first band (11; 13) is secured on a suitable location of the end piece (7; 8) and an end of the second band (12; 14) is secured on a different suitable location of the end piece (7; 8), whereby the other end of the bands (11, 12, 13, 14) is connected with the allocated element (18; 19, 20).
 5. Apparatus according to claim 4, characterized in that the band (12) crossingly penetrates through the band (11), and the band (14) crossingly penetrates through the band (13).
 6. Apparatus according to claim 5, characterized in that the first band (11; 13) is wider than the second band (12; 14).
 7. Apparatus according to claim 4, characterized in that the first band (11; 13) comprises a slot (17) that extends over a major portion of the first band's length, of which slot the width is larger than the width of the second band (12; 14).
 8. Apparatus according to claim 1, characterized in that the bands (11, 12; 13, 14) are arranged next to one another.
 9. Apparatus according to claim 8, characterized in that the bands (11, 12; 13, 14) are embodied equally wide.
 10. Apparatus according to claim 1, characterized in that the bands (11, 12; 13, 14) consist of steel, synthetic plastic, or of textile material.
 11. Apparatus according to claim 10, characterized in that the bands consist of its combination of these materials. 